1. Field of the Art
The subject invention is in the field of latches which prevent motion of one piece of apparatus relative to another until the latch is operated. More specifically it is in the field of latches used with apparatus in telescopic engagement to prevent telescopic relative motion until the latch is operated.
2. Prior Art
The prior art for this invention, even in the more specific field, is profuse. A most pertinent example, however, is the latch used in an invention by the subject inventor, the invention being the subject of U.S. Pat. No. 4,534,449, entitled "Perforating Seal Greasing Apparatus and Method." Elements are telescopically engaged and a latch prevents relative motion between them. It has been found that the competition in the marketing of inventions, such as that of U.S. Pat. No. 4,534,449, is such that the cost of manufacture of such devices is of unusual significance. This is particularly true when the product is intended in part for non-professional uses undertaken for the express purpose of conserving costs. Therefore, the primary problem leading to the subject invention was the reduction of the costs of manufacture.
It has been recognized that costs can be reduced by manufacturing at least the telescopic parts by injection molding of plastics. It has also been recognized that the costs can be still further reduced by mass production using injection molding and by the reduction of the number of separate parts to be manufactured, assembled, inventoried, etc.